Due to environmental pollution, car exhaust gases and the like, hormone imbalance conditions are becoming severe. For this reason, the incidence of hair loss is increasing, the age of people with hair loss is decreasing, and various skin diseases are being caused due to the inability of the skin immune system. Thus, extensive studies have been conducted to develop materials that can provide a beautiful appearance and can effectively solve various phenomena that are serious social problems, for example, wrinkle formation by intrinsic aging and UV rays, immune imbalance, and hair loss.
Wrinkles are caused by aging of the skin, and aged skin is a result of the natural changes associated with the process of aging. Skin aging is roughly classified into two categories: physiological aging that shows an age-related change in the skin's function, structure or shape throughout the skin surface, and photoaging caused by UV rays.
As skin aging progresses, a significant change in the dermis appears. Dermal atrophy appearing in people 70 years of age or older is a typical aging phenomenon. Changes in the dermis result from changes in high-molecular-weight substances in the extracellular matrix due to decreases in the number of fibroblasts and the ability to form fibroblasts. Specific examples of these changes include separation of collagen bundles, a decrease in mucopolysaccharide synthesis, decreases in the number and diameter of collagen and elastin, decomposition of collagen and elastin, and blood vessel expansion. Generally, among various factors, including the skin's moisture content, collagen content and immune responses to external environments, the expression level and activity of collagenase, a collagen-degrading enzyme that reduces the production and content of collagen, has the greatest effect on the formation of wrinkles.
Methods for preventing wrinkles include a method of using an antioxidant that inhibits the generation of reactive oxygen species to prevent cell aging, a peeling method in which the skin is peeled off using chemicals such as hydroxyl acid (glycolic acid) or beta-hydroxyl acid (salicylic acid) to reduce thin wrinkles on the skin, a Botox therapy in which a specific amount of botulinum toxin is injected into wrinkled facial muscles to reduce wrinkles, and a filler method in which a wrinkled area is filled with a material such as hyaluronic acid to alleviate wrinkles.
The above methods have an insignificant effect on the alleviation of wrinkles, or when they are excessively used, they cause side effects and are problematic in terms of stability and safety. For this reason, there is a need for the development of compositions that are derived from natural materials, have less side effects, are safe, and have an excellent effect of reducing wrinkles.
The term “alopecia” refers to a state in which hairs are not present in regions which should have hair, and more particularly to loss of terminal hairs from the scalp. Alopecia (hair loss) is caused mainly by genetic factors and the male hormone androgen. Tissues associated with androgen include sebaceous gland, keratinocytes of the epidermis and hair follicle, dermal papilla cells, sweat glands, root sheath of the scalp hair follicle, etc.
It was reported that the activity of 5-α-reductase in the tissue of a region with alopecia is generally higher than that in the tissue of a region having hair. 5-α-reductase acts to reduce testosterone into dehydrotestosterone (DHT), and it is known that testosterone is involved in an increase in skeletal muscles, sperm formation and the like in the secondary sex character of males, and dehydrotestosterone is involved in acne, an increase in sebum, alopecia and benign prostatic hyperplasia (J. Invest. Dermatol. 1995; 105(2): 209-14). Thus, many studies have been conducted to find pharmacologically active substances that treat alopecia by inhibiting the activity of 5-α-reductase that is involved in the reduction of testosterone into dehydrotestosterone.
Conventional inhibitors of 5-α-reductase include compounds such as finasteride and are used as prostate therapeutic agents and alopecia preventive agents at different doses. Finasteride is excellent in terms of convenience and efficacy, but has a problem in that it is prepared using expensive or highly toxic reagents, which increase the production cost or cause environmental pollution. Particularly, it has problems in that it is not easy to remove byproducts, resulting in a decrease in the purity of the desired product, or reagents or active derivatives that are readily deteriorated by water are used, making it difficult to produce finasteride. In addition, steroidal hormones themselves play an important role in normal physiological activity, and thus when the production of steroidal hormones is artificially blocked, various problems can arise.
Thus, there is a need to develop substances that stimulate the secretion of growth factors, which stimulate the proliferation of dermal papilla cells or are helpful in the proliferation, and at the same time, inhibit the biosynthesis of TGF-beta-1 that is a signaling substance downstream of 5-α-reductase, rather than developing substances that inhibit the activity of 5-α-reductase.
With respect to methods for reducing skin wrinkles, preventing hair loss and promoting hair growth, Korean Patent Registration No. 0868784 discloses a cosmetic composition for reducing skin wrinkles, which contains an extract of Rhodotus palmatus cultured broth, and Korean Patent Laid-Open Publication No. 2007-0123712 discloses a cosmetic composition for preventing skin aging, which contains Rambutan and Lychee extracts as active ingredients. Further, Korean Patent Laid-Open Publication No. 2010-0119226 discloses a composition for preventing hair loss and promoting hair growth, which contains a seaweed extract, and Korean Patent Laid-Open Publication No. 2004-0097416 discloses a health functional food for preventing and ameliorating hair loss and seborrheic skin conditions, which contains an Actinidia extract. Moreover, Korean Patent Laid-Open Publication No. 2011-0078678 discloses a cosmetic composition for reducing wrinkles, which contains an isoflavone aglycone, and Korean Patent Laid-Open Publication No. 2008-0069816 discloses a composition for reducing skin wrinkles and improving skin elasticity, which contains a Puer tea extract. In addition, Korean Patent Laid-Open Publication No. 2009-0021963 discloses a composition for preventing hair loss and promoting hair growth, which contains, as an active ingredient, one or more of a 2-methyl-hept-2-ene derivative and linalool oxide, and Korean Patent Laid-Open Publication No. 2012-0039384 discloses a composition for promoting hair growth, which contains flavonoid.
However, a method for blocking UV rays, reducing skin wrinkles, promoting hair growth and preventing hair loss using veratric acid or acceptable salt thereof as disclosed in the present invention has not yet been disclosed.
Accordingly, the present inventors have made extensive efforts to develop a plant-derived composition for improving skin conditions, which is based on a natural material and harmless to the human body and has excellent safety, stability and effects. As a result, the present inventors have found that a composition containing veratric acid or acceptable salt thereof as an active ingredient is very effective for protection from UV rays, the reduction of skin wrinkles, the promotion of hair growth and the prevention of hair loss, thereby completing the present invention.